Eh you're no failure. I had the same problems you have. The biggest thing is your outlook. Maybe people just told you all these bad things about yourself and you believed them. That's really easy to do. But thinking you're a failure because you don't have a girlfriend or because you have social anxiety isn't right either because you base your self-worth on other people instead of who you are as a person. Who you are as a person is what counts. Feeling better about yourself is really key. Relationships should be pursued as something to add on to life and not something to "fill a hole."

Don't try to be something you're not. You'll end up being something you don't intend to be. I'm not sure why that is but it always ends in the worst way possible so just don't do that. Try to find your own interests right now and find things to enhance your life. That is much more important than getting a girlfriend right now. You have to come first. As long as you have doubts about yourself social anxiety is going to be rough. But that's the key to getting better. Working on that anxiety and pulling up that self-esteem goes a really long way. You may not completely rid yourself of it and that's pretty normal. As long as you can find ways to start liking yourself things will get better.